The present invention relates generally to the field of rail transportation, and more specifically to on-board systems for treating the rail directly in front of a locomotive wheel, and in particular, to verifying the proper alignment of a nozzle of a locomotive rail treatment apparatus.
Modem locomotives are commonly powered by electric traction motors coupled via suitable gearing to one or more axles of the vehicle. In the motoring mode of operation, the traction motors are supplied with electric current from a controllable source of electric power, such as an engine-driven alternator, to rotate the axle. The axle drives a wheel which, in turn, supports the locomotive on the rail and propels the vehicle along the track. In the braking mode of operation, the electric motor may have its mode changed to function as a generator to assist the mechanical brakes in slowing the speed of the locomotive. In any mode of operation, good adhesion between the wheel and the rail is required for efficient operation of the vehicle. The peak pulling and braking capability of the locomotive may be limited by the adhesion available between the drive wheels and the rails. Contaminants such as snow, water, grease, insects and rust that are present on the rail can reduce the maximum available adhesion.
Systems for treating the rail directly in front of a rail vehicle wheel in order to improve adhesion between the wheel and the rail are well known in the art. The use of compressed air and steam to clean the rail in a railroad system began in the 1,800""s. Modern locomotives are often equipped with a sanding system and a rail cleaning system. A cleaning system may include a supply of compressed air selectively delivered to a nozzle having an outlet directly in front of a drive wheel. The nozzle directs a blast of compressed air against the rail at a predetermined angle of attack in order to displace contaminants from the rail. Such cleaning systems are often used to remove accumulations of snow in cold environments. A sanding system may include a supply of sand or other particulate matter selectively delivered to a nozzle having an outlet directly in front of a drive wheel. The nozzle directs a quantity of sand between the rail and the wheel. The sand improves the adhesion between the wheel and the rail, particularly in the presence of snow, ice or grease.
The proper operation of rail treatment systems is important for minimizing the number of adhesion-related stalls that occur on a railway. This is particularly true for railroads in cold climates where snow and ice are a constant challenge. Such systems must be routinely inspected and maintained to ensure that the outlet nozzle of the system is properly aligned with respect to the wheel and the rail so that the material delivered by the nozzle is used effectively. The term xe2x80x9cmaterialxe2x80x9d as used herein with respect to a rail conditioning system is meant to be inclusive of the sand, steam, compressed air, adhesion product, or other matter that is expelled from a nozzle of a rail conditioning system and directed toward the rail or wheel for accomplishing a desired treatment.
FIG. 1 is an example of a prior art rail conditioning system nozzle alignment verification system 10, in this case applied to a sand application system 11. A locomotive includes a drive wheel 12 and a sand nozzle 14 having an outlet 16 for directing a diffused spray 18 of adhesion-enhancing material toward a rail 20 directly in front of the wheel 12. The diffused spray 18 will have a distribution pattern that is determined by the geometry of the nozzle outlet 16 and that is selected by the system designer to provide a preferred pattern of adhesion-enhancing material on the rail 20. A centerline C/LN of the nozzle outlet 16 and of the diffused spray 18 may be aligned with a centerline C/LW of the wheel 12 for proper application of the adhesion-enhancing material. An alignment tool 22 includes a body member 24 designed to fit over the nozzle and an elongated handle 24 attached to the body 24 for manipulation by an inspector. The alignment tool 22 also includes a pointer 28 connected to the body 24 and extending in the direction of the material spray 18. Pointer 28 is designed to have a shape that places its tip 30 along the centerline C/LN of the diffused spray 18 at a predetermined distance from the nozzle outlet 16. An inspector may determine if the sand nozzle 14 is properly aligned by viewing the location of the tip 30 of the pointer 28 relative to the rail 20. In the event that the nozzle 14 is not properly aligned, the handle 26 also provides leverage for the inspector to apply a force for bending the sand delivery tube 32 to achieve proper alignment of the nozzle outlet 16.
Prior art rail conditioning system nozzle alignment verification system 10 is more effective as an adjustment tool than as an inspection tool. A typical sand delivery tube 32 may be a steel tube having and outside diameter of 1.25 inches and an inside diameter of {fraction (15/16)} inch. The tube 32 has such a sturdy construction in order to be able to minimize damage due to impacts with passing objects. In order to bend such a pipe for alignment purposes, it is necessary to apply a considerable amount of force while the material is heated to a red-hot condition. Alignment tool 22 functions as a large pry bar for exerting such force. There is a necessary gap between the inside dimension of the alignment tool body 24 and the outside dimension of the sand nozzle 14 in order for the tool 22 to fit over the nozzle 14. This gap allows the body 24 to wobble relative to the true centerline C/LN of the nozzle outlet 16, and that movement is exaggerated at the pointer tip 30. Thus, the combination of a bending tool and an alignment mechanism into a single tool 22 results in a poor alignment guide. Alignment of the nozzle 14 may be expected to have an uncertainty of up to xc2x1xc2xd inch where the adhesion material strikes the rail 20 as a result of this movement. Furthermore, the alignment tool 22 is heavy and awkward for the inspector to use, since it must be able to withstand the forces necessary for bending the delivery tube 32 when adjustment is required.
FIG. 1 also illustrates the location of the outlet nozzle 34 of a type of rail cleaning system 35 called a Snow Blaster. A diffused pattern of compressed air 36 is generated by the nozzle 34 which receives the air through a delivery pipe 38. The delivery pipe 38 may typically be a xc2xd inch schedule 80 steel tube with a xc2xd inch union welded onto an end to accept the nozzle 34. The delivery pipe 38 is attached to the sand pipe support bracket, which in turn is attached to the truck at the journal box (not shown). The compressed air 36 is directed toward the rail 20 at an angle with respect to the longitudinal axis of the rail 20 and with respect to a vertical axis through the rail 20. The compressed air 36 is used to remove snow and ice from the rail directly in front of the locomotive wheel 12. Current operating procedures require the nozzle 34 to be removed for cleaning and inspection on a periodic basis. The alignment of the nozzle 34 is also visually checked at that time and any gross misalignment corrected. Delivery pipe 38 must be heated to a red-hot condition and bent to change the alignment of the nozzle 34. No process currently exists for accurately determining the alignment of the nozzle 34 with respect to the rail 20.
One may appreciate that the operating environment of the nozzles 14, 34 of a rail conditioning system can be quite harsh. The nozzles 14, 34 are exposed to atmospheric conditions including rain, snow and temperature extremes. They are also subject to impact with foreign objects in the path of the rail 20 and with debris that is dislodged by the moving locomotive, for example rocks, litter and ice. As a result, it is not uncommon for such nozzles to become misaligned. Misalignment of rail conditioning nozzles has been known to contribute directly to adhesion related locomotive stalls, thereby adversely affecting the service level for the railroad. Current methods for checking the alignment of rail conditioning nozzles are at best cumbersome and inaccurate, and they are at worst nonexistent. Because the consequences of a misaligned nozzle can be significant, it is necessary to perform an inspection of such nozzles regularly. A convenient, accurate method for confirming the proper alignment of such nozzles is needed.
Laser alignment systems are well known. U.S. Pat. No. 6,286,219 describes a laser alignment method and apparatus for aligning a series of pipes with respect to each other during the assembly of a fire sprinkler system. A laser light source is affixed to an open end of a pipe, and a mating pipe end is positioned with respect to the laser light beam. U.S. Pat. No. 6,151,788 describes a laser beam used for alignment of a gun sight. A source of laser light is placed inside the gun barrel and the gun sight is adjusted so that the light beam is aligned with a target. U.S. Pat. No. 5,675,899 describes a rotary saw that is guided so that a laser light beam follows a target in order to align the saw blade properly. In spite of the need for improved nozzle alignment systems for a locomotive application, the present inventor is not aware of any application of a laser for improving the delivery of material from a rail conditioning device.
A method and apparatus for aligning a rail conditioning system installed on a rail vehicle for delivery of a rail conditioning material to a desired location on a rail relative to a wheel of the rail vehicle are described herein. Such a rail conditioning system includes a delivery conduit having a nozzle for producing a diffused spray of a material centered along a line of flow directed toward the rail. The method may include: removing a nozzle from a delivery conduit of a rail conditioning system of a rail vehicle; detachably securing a source of light on the delivery conduit in place of the nozzle to unmovingly align the source of light relative to the delivery conduit; energizing the source of light to direct a beam of light along a path corresponding to a central line of a flow of material to be delivered by the nozzle; detecting impingement of the beam of light on one of a rail and a wheel to assess alignment of the nozzle when installed on the delivery conduit for centering the flow of material on a desired location; removing the source of light from the delivery conduit; reinstalling the nozzle onto the delivery conduit; and delivering a spray of a rail conditioning material to provide a desired coverage of the rail by the rail conditioning material. The method may include performing the steps of detachably securing a source of light, energizing the source of light, detecting impingement of the beam of light, and removing the source of light during a service event when the nozzle is otherwise removed from the delivery conduit for servicing. The method may include: removing the nozzle from the delivery conduit by unthreading the nozzle; attaching the source of light to a fixture provided with threads; and threading the fixture onto the conduit in place of the nozzle.
A method of aligning a rail conditioning system installed on a rail vehicle for delivery of a rail conditioning material to a desired location on a rail relative to a wheel of the rail vehicle is described herein. The rail conditioning system may include a delivery conduit having a nozzle for producing a diffused spray of a material centered along a line of flow directed toward the rail, and the method may include: detachably securing a source of light to be unmovingly aligned with a nozzle end of a conduit of a rail conditioning system; energizing the source of light to direct a beam of light along a path corresponding to a central line of flow of a diffused spray of material to be delivered by the conduit through a nozzle; detecting impingement of the beam of light on one of a rail and a wheel to assess alignment of the nozzle for centering the flow of material on a desired region of the rail; and delivering a spray of rail conditioning material to the rail through the nozzle to provide a desired coverage of the rail by the rail conditioning material. The method may include: removing the nozzle from the conduit prior to the step of detachably securing the source of light; detachably securing the source of light in place of the nozzle; and reattaching the nozzle between the steps of detecting impingement and delivering a spray of rail conditioning material. The method may include: attaching the source of light to a fitting having a generally hollow shape adapted for receiving the nozzle; and detachably securing the source of light by placing the fitting over the nozzle. The fitting may be formed to contain a notch in a predetermined location; and the method may include aligning the fitting on the nozzle by engaging a protruding feature of the nozzle into the notch.
A method of aligning a rail conditioning system installed on a rail vehicle for delivery of a rail conditioning material to a desired location on a rail is described herein, the rail conditioning system including a delivery conduit having a nozzle for producing a diffused spray of a material centered along a line of flow directed toward the rail, the method includes: adjusting alignment of a conduit to have approximately a first predetermined angle in a forward direction and to have approximately a second predetermined angle in a sideward direction with respect to a vertical axis passing through a rail; removing an outlet nozzle from the conduit; unmovingly securing a source of light on the conduit in place of the nozzle; energizing the source of light to direct a beam of light along a path corresponding to a central line of a flow of material to be delivered by the nozzle; adjusting alignment of the conduit to direct impingement of the beam of light onto a predetermined location; removing the source of light from the delivery conduit; and reinstalling the nozzle onto the delivery conduit.
An apparatus for aligning a rail conditioning system installed on a rail vehicle for delivery of a rail conditioning material to a desired location on a rail is described herein, the rail conditioning system including a delivery conduit having a nozzle for producing a diffused spray of a material centered along a line of flow directed toward the rail, the apparatus including: a fitting for removable attachment to a conduit of a rail conditioning system; and a source of light attached to the fitting for directing a beam of light in unmoving alignment with a central line of a flow of material to be delivered through the conduit.
The fitting may further include a generally hollow shape adapted for fitting over portion of a nozzle attached to the conduit. The fitting may include a notch formed in the fitting for engagement with a protruding member of the nozzle for alignment of the source of light along the line of flow. When a nozzle is threaded into the conduit, and the fitting may include threads adapted to thread into the conduit in place of the nozzle. The source of light may include a battery-operated laser.